How can I combine an animation with transparent background and a pre-rendered scene(panoramic camera)(VR Video)?
To lay the Video clip on the Background


The picture above will be the result.

Node Setup

Switch to Compositing, and click on Use Node

Set it up like this.

Step by step of setting your node

To get the Viewer


To get Alpha Over


To add your Image


To fit your Image to Scene Size

I use Render Layer,
But in your case, you need to load the clip to Motion Tracking since you have rendered it.

Then you need to Add Movie Clip from the Compositing Panel as indicated, and replace it with my Render Layer Node